SIP 183 Session Progress vs 608 Rejected
SIP 183 (Session Progress) is a 1xx Provisional response, while 608 (Rejected) is a 6xx Global Failure response. 183 indicates that used to convey information about the progress of the call that is not otherwise classified. Often carries early media (ringback tones, announcements) via SDP. In contrast, 608 means that an intermediary machine or process rejected the call attempt. Similar to 607 but the rejection comes from the network rather than the end user.
Описание
Used to convey information about the progress of the call that is not otherwise classified. Often carries early media (ringback tones, announcements) via SDP.
Когда вы это видите
During call setup, especially in PSTN interworking scenarios. The response may contain SDP for early media like custom ringback tones or IVR prompts.
Как исправить
No fix needed — this is informational. If early media is not playing, check codec negotiation and SDP handling in your UA.
Описание
An intermediary machine or process rejected the call attempt. Similar to 607 but the rejection comes from the network rather than the end user.
Когда вы это видите
When a network element (not the callee) blocks the call. Used by analytics engines and call-blocking services in the network path.
Как исправить
This is a network-level block. Contact the network administrator or carrier to understand why the call was blocked.
Ключевые различия
183 is a 1xx Provisional response, while 608 is a 6xx Global Failure response.
SIP 183: Used to convey information about the progress of the call that is not otherwise classified. Often carries early media (ringback tones, announcements) via SDP.
SIP 608: An intermediary machine or process rejected the call attempt. Similar to 607 but the rejection comes from the network rather than the end user.
You encounter 183 when during call setup, especially in PSTN interworking scenarios. The response may contain SDP for early media like custom ringback tones or IVR prompts.
You encounter 608 when when a network element (not the callee) blocks the call. Used by analytics engines and call-blocking services in the network path.
Когда что использовать
For 183 (Session Progress): No fix needed — this is informational. If early media is not playing, check codec negotiation and SDP handling in your UA. For 608 (Rejected): This is a network-level block. Contact the network administrator or carrier to understand why the call was blocked.